crypto: aesni - Convert rfc4106 to new AEAD interface

This patch converts the low-level __gcm-aes-aesni algorithm to
the new AEAD interface.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

arch/x86/crypto/aesni-intel_glue.c

@@ -44,13 +44,18 @@
 #endif
 
 
+#define AESNI_ALIGN	16
+#define AES_BLOCK_MASK	(~(AES_BLOCK_SIZE - 1))
+#define RFC4106_HASH_SUBKEY_SIZE 16
+
 /* This data is stored at the end of the crypto_tfm struct.
  * It's a type of per "session" data storage location.
  * This needs to be 16 byte aligned.
  */
 struct aesni_rfc4106_gcm_ctx {
-	u8 hash_subkey[16];
-	struct crypto_aes_ctx aes_key_expanded;
+	u8 hash_subkey[16] __attribute__ ((__aligned__(AESNI_ALIGN)));
+	struct crypto_aes_ctx aes_key_expanded
+		__attribute__ ((__aligned__(AESNI_ALIGN)));
 	u8 nonce[4];
 };
 
@@ -65,10 +70,6 @@ struct aesni_hash_subkey_req_data {
 	struct scatterlist sg;
 };
 
-#define AESNI_ALIGN	(16)
-#define AES_BLOCK_MASK	(~(AES_BLOCK_SIZE-1))
-#define RFC4106_HASH_SUBKEY_SIZE 16
-
 struct aesni_lrw_ctx {
 	struct lrw_table_ctx lrw_table;
 	u8 raw_aes_ctx[sizeof(struct crypto_aes_ctx) + AESNI_ALIGN - 1];
@@ -282,10 +283,11 @@ static void (*aesni_gcm_dec_tfm)(void *ctx, u8 *out,
 static inline struct
 aesni_rfc4106_gcm_ctx *aesni_rfc4106_gcm_ctx_get(struct crypto_aead *tfm)
 {
-	return
-		(struct aesni_rfc4106_gcm_ctx *)
-		PTR_ALIGN((u8 *)
-		crypto_tfm_ctx(crypto_aead_tfm(tfm)), AESNI_ALIGN);
+	unsigned long align = AESNI_ALIGN;
+
+	if (align <= crypto_tfm_ctx_alignment())
+		align = 1;
+	return PTR_ALIGN(crypto_aead_ctx(tfm), align);
 }
 #endif
 
@@ -838,8 +840,6 @@ rfc4106_set_hash_subkey(u8 *hash_subkey, const u8 *key, unsigned int key_len)
 	if (IS_ERR(ctr_tfm))
 		return PTR_ERR(ctr_tfm);
 
-	crypto_ablkcipher_clear_flags(ctr_tfm, ~0);
-
 	ret = crypto_ablkcipher_setkey(ctr_tfm, key, key_len);
 	if (ret)
 		goto out_free_ablkcipher;
@@ -888,56 +888,20 @@ rfc4106_set_hash_subkey(u8 *hash_subkey, const u8 *key, unsigned int key_len)
 static int common_rfc4106_set_key(struct crypto_aead *aead, const u8 *key,
 				  unsigned int key_len)
 {
-	int ret = 0;
-	struct crypto_tfm *tfm = crypto_aead_tfm(aead);
 	struct aesni_rfc4106_gcm_ctx *ctx = aesni_rfc4106_gcm_ctx_get(aead);
-	u8 *new_key_align, *new_key_mem = NULL;
 
 	if (key_len < 4) {
-		crypto_tfm_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+		crypto_aead_set_flags(aead, CRYPTO_TFM_RES_BAD_KEY_LEN);
 		return -EINVAL;
 	}
 	/*Account for 4 byte nonce at the end.*/
 	key_len -= 4;
-	if (key_len != AES_KEYSIZE_128 && key_len != AES_KEYSIZE_192 &&
-	    key_len != AES_KEYSIZE_256) {
-		crypto_tfm_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
-		return -EINVAL;
-	}
 
 	memcpy(ctx->nonce, key + key_len, sizeof(ctx->nonce));
-	/*This must be on a 16 byte boundary!*/
-	if ((unsigned long)(&(ctx->aes_key_expanded.key_enc[0])) % AESNI_ALIGN)
-		return -EINVAL;
-
-	if ((unsigned long)key % AESNI_ALIGN) {
-		/*key is not aligned: use an auxuliar aligned pointer*/
-		new_key_mem = kmalloc(key_len+AESNI_ALIGN, GFP_KERNEL);
-		if (!new_key_mem)
-			return -ENOMEM;
-
-		new_key_align = PTR_ALIGN(new_key_mem, AESNI_ALIGN);
-		memcpy(new_key_align, key, key_len);
-		key = new_key_align;
-	}
 
-	if (!irq_fpu_usable())
-		ret = crypto_aes_expand_key(&(ctx->aes_key_expanded),
-		key, key_len);
-	else {
-		kernel_fpu_begin();
-		ret = aesni_set_key(&(ctx->aes_key_expanded), key, key_len);
-		kernel_fpu_end();
-	}
-	/*This must be on a 16 byte boundary!*/
-	if ((unsigned long)(&(ctx->hash_subkey[0])) % AESNI_ALIGN) {
-		ret = -EINVAL;
-		goto exit;
-	}
-	ret = rfc4106_set_hash_subkey(ctx->hash_subkey, key, key_len);
-exit:
-	kfree(new_key_mem);
-	return ret;
+	return aes_set_key_common(crypto_aead_tfm(aead),
+				  &ctx->aes_key_expanded, key, key_len) ?:
+	       rfc4106_set_hash_subkey(ctx->hash_subkey, key, key_len);
 }
 
 static int rfc4106_set_key(struct crypto_aead *parent, const u8 *key,
@@ -960,7 +924,7 @@ static int common_rfc4106_set_authsize(struct crypto_aead *aead,
 	default:
 		return -EINVAL;
 	}
-	crypto_aead_crt(aead)->authsize = authsize;
+
 	return 0;
 }
 
@@ -975,20 +939,17 @@ static int rfc4106_set_authsize(struct crypto_aead *parent,
 	return crypto_aead_setauthsize(&cryptd_tfm->base, authsize);
 }
 
-static int __driver_rfc4106_encrypt(struct aead_request *req)
+static int helper_rfc4106_encrypt(struct aead_request *req)
 {
 	u8 one_entry_in_sg = 0;
 	u8 *src, *dst, *assoc;
 	__be32 counter = cpu_to_be32(1);
 	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 	struct aesni_rfc4106_gcm_ctx *ctx = aesni_rfc4106_gcm_ctx_get(tfm);
-	u32 key_len = ctx->aes_key_expanded.key_length;
 	void *aes_ctx = &(ctx->aes_key_expanded);
 	unsigned long auth_tag_len = crypto_aead_authsize(tfm);
-	u8 iv_tab[16+AESNI_ALIGN];
-	u8* iv = (u8 *) PTR_ALIGN((u8 *)iv_tab, AESNI_ALIGN);
+	u8 iv[16] __attribute__ ((__aligned__(AESNI_ALIGN)));
 	struct scatter_walk src_sg_walk;
-	struct scatter_walk assoc_sg_walk;
 	struct scatter_walk dst_sg_walk;
 	unsigned int i;
 
@@ -997,12 +958,6 @@ static int __driver_rfc4106_encrypt(struct aead_request *req)
 	/* to 8 or 12 bytes */
 	if (unlikely(req->assoclen != 8 && req->assoclen != 12))
 		return -EINVAL;
-	if (unlikely(auth_tag_len != 8 && auth_tag_len != 12 && auth_tag_len != 16))
-	        return -EINVAL;
-	if (unlikely(key_len != AES_KEYSIZE_128 &&
-	             key_len != AES_KEYSIZE_192 &&
-	             key_len != AES_KEYSIZE_256))
-	        return -EINVAL;
 
 	/* IV below built */
 	for (i = 0; i < 4; i++)
@@ -1011,55 +966,57 @@ static int __driver_rfc4106_encrypt(struct aead_request *req)
 		*(iv+4+i) = req->iv[i];
 	*((__be32 *)(iv+12)) = counter;
 
-	if ((sg_is_last(req->src)) && (sg_is_last(req->assoc))) {
+	if (sg_is_last(req->src) &&
+	    req->src->offset + req->src->length <= PAGE_SIZE &&
+	    sg_is_last(req->dst) &&
+	    req->dst->offset + req->dst->length <= PAGE_SIZE) {
 		one_entry_in_sg = 1;
 		scatterwalk_start(&src_sg_walk, req->src);
-		scatterwalk_start(&assoc_sg_walk, req->assoc);
-		src = scatterwalk_map(&src_sg_walk);
-		assoc = scatterwalk_map(&assoc_sg_walk);
+		assoc = scatterwalk_map(&src_sg_walk);
+		src = assoc + req->assoclen;
 		dst = src;
 		if (unlikely(req->src != req->dst)) {
 			scatterwalk_start(&dst_sg_walk, req->dst);
-			dst = scatterwalk_map(&dst_sg_walk);
+			dst = scatterwalk_map(&dst_sg_walk) + req->assoclen;
 		}
-
 	} else {
 		/* Allocate memory for src, dst, assoc */
-		src = kmalloc(req->cryptlen + auth_tag_len + req->assoclen,
+		assoc = kmalloc(req->cryptlen + auth_tag_len + req->assoclen,
 			GFP_ATOMIC);
-		if (unlikely(!src))
+		if (unlikely(!assoc))
 			return -ENOMEM;
-		assoc = (src + req->cryptlen + auth_tag_len);
-		scatterwalk_map_and_copy(src, req->src, 0, req->cryptlen, 0);
-		scatterwalk_map_and_copy(assoc, req->assoc, 0,
-					req->assoclen, 0);
+		scatterwalk_map_and_copy(assoc, req->src, 0,
+					 req->assoclen + req->cryptlen, 0);
+		src = assoc + req->assoclen;
 		dst = src;
 	}
 
+	kernel_fpu_begin();
 	aesni_gcm_enc_tfm(aes_ctx, dst, src, (unsigned long)req->cryptlen, iv,
 		ctx->hash_subkey, assoc, (unsigned long)req->assoclen, dst
 		+ ((unsigned long)req->cryptlen), auth_tag_len);
+	kernel_fpu_end();
 
 	/* The authTag (aka the Integrity Check Value) needs to be written
 	 * back to the packet. */
 	if (one_entry_in_sg) {
 		if (unlikely(req->src != req->dst)) {
-			scatterwalk_unmap(dst);
-			scatterwalk_done(&dst_sg_walk, 0, 0);
+			scatterwalk_unmap(dst - req->assoclen);
+			scatterwalk_advance(&dst_sg_walk, req->dst->length);
+			scatterwalk_done(&dst_sg_walk, 1, 0);
 		}
-		scatterwalk_unmap(src);
 		scatterwalk_unmap(assoc);
-		scatterwalk_done(&src_sg_walk, 0, 0);
-		scatterwalk_done(&assoc_sg_walk, 0, 0);
+		scatterwalk_advance(&src_sg_walk, req->src->length);
+		scatterwalk_done(&src_sg_walk, req->src == req->dst, 0);
 	} else {
-		scatterwalk_map_and_copy(dst, req->dst, 0,
-			req->cryptlen + auth_tag_len, 1);
-		kfree(src);
+		scatterwalk_map_and_copy(dst, req->dst, req->assoclen,
+					 req->cryptlen + auth_tag_len, 1);
+		kfree(assoc);
 	}
 	return 0;
 }
 
-static int __driver_rfc4106_decrypt(struct aead_request *req)
+static int helper_rfc4106_decrypt(struct aead_request *req)
 {
 	u8 one_entry_in_sg = 0;
 	u8 *src, *dst, *assoc;
@@ -1068,26 +1025,16 @@ static int __driver_rfc4106_decrypt(struct aead_request *req)
 	int retval = 0;
 	struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 	struct aesni_rfc4106_gcm_ctx *ctx = aesni_rfc4106_gcm_ctx_get(tfm);
-	u32 key_len = ctx->aes_key_expanded.key_length;
 	void *aes_ctx = &(ctx->aes_key_expanded);
 	unsigned long auth_tag_len = crypto_aead_authsize(tfm);
-	u8 iv_and_authTag[32+AESNI_ALIGN];
-	u8 *iv = (u8 *) PTR_ALIGN((u8 *)iv_and_authTag, AESNI_ALIGN);
-	u8 *authTag = iv + 16;
+	u8 iv[16] __attribute__ ((__aligned__(AESNI_ALIGN)));
+	u8 authTag[16];
 	struct scatter_walk src_sg_walk;
-	struct scatter_walk assoc_sg_walk;
 	struct scatter_walk dst_sg_walk;
 	unsigned int i;
 
-	if (unlikely((req->cryptlen < auth_tag_len) ||
-		(req->assoclen != 8 && req->assoclen != 12)))
+	if (unlikely(req->assoclen != 8 && req->assoclen != 12))
 		return -EINVAL;
-	if (unlikely(auth_tag_len != 8 && auth_tag_len != 12 && auth_tag_len != 16))
-	        return -EINVAL;
-	if (unlikely(key_len != AES_KEYSIZE_128 &&
-	             key_len != AES_KEYSIZE_192 &&
-	             key_len != AES_KEYSIZE_256))
-	        return -EINVAL;
 
 	/* Assuming we are supporting rfc4106 64-bit extended */
 	/* sequence numbers We need to have the AAD length */
@@ -1101,33 +1048,36 @@ static int __driver_rfc4106_decrypt(struct aead_request *req)
 		*(iv+4+i) = req->iv[i];
 	*((__be32 *)(iv+12)) = counter;
 
-	if ((sg_is_last(req->src)) && (sg_is_last(req->assoc))) {
+	if (sg_is_last(req->src) &&
+	    req->src->offset + req->src->length <= PAGE_SIZE &&
+	    sg_is_last(req->dst) &&
+	    req->dst->offset + req->dst->length <= PAGE_SIZE) {
 		one_entry_in_sg = 1;
 		scatterwalk_start(&src_sg_walk, req->src);
-		scatterwalk_start(&assoc_sg_walk, req->assoc);
-		src = scatterwalk_map(&src_sg_walk);
-		assoc = scatterwalk_map(&assoc_sg_walk);
+		assoc = scatterwalk_map(&src_sg_walk);
+		src = assoc + req->assoclen;
 		dst = src;
 		if (unlikely(req->src != req->dst)) {
 			scatterwalk_start(&dst_sg_walk, req->dst);
-			dst = scatterwalk_map(&dst_sg_walk);
+			dst = scatterwalk_map(&dst_sg_walk) + req->assoclen;
 		}
 
 	} else {
 		/* Allocate memory for src, dst, assoc */
-		src = kmalloc(req->cryptlen + req->assoclen, GFP_ATOMIC);
-		if (!src)
+		assoc = kmalloc(req->cryptlen + req->assoclen, GFP_ATOMIC);
+		if (!assoc)
 			return -ENOMEM;
-		assoc = (src + req->cryptlen);
-		scatterwalk_map_and_copy(src, req->src, 0, req->cryptlen, 0);
-		scatterwalk_map_and_copy(assoc, req->assoc, 0,
-			req->assoclen, 0);
+		scatterwalk_map_and_copy(assoc, req->src, 0,
+					 req->assoclen + req->cryptlen, 0);
+		src = assoc + req->assoclen;
 		dst = src;
 	}
 
+	kernel_fpu_begin();
 	aesni_gcm_dec_tfm(aes_ctx, dst, src, tempCipherLen, iv,
 		ctx->hash_subkey, assoc, (unsigned long)req->assoclen,
 		authTag, auth_tag_len);
+	kernel_fpu_end();
 
 	/* Compare generated tag with passed in tag. */
 	retval = crypto_memneq(src + tempCipherLen, authTag, auth_tag_len) ?
@@ -1135,16 +1085,17 @@ static int __driver_rfc4106_decrypt(struct aead_request *req)
 
 	if (one_entry_in_sg) {
 		if (unlikely(req->src != req->dst)) {
-			scatterwalk_unmap(dst);
-			scatterwalk_done(&dst_sg_walk, 0, 0);
+			scatterwalk_unmap(dst - req->assoclen);
+			scatterwalk_advance(&dst_sg_walk, req->dst->length);
+			scatterwalk_done(&dst_sg_walk, 1, 0);
 		}
-		scatterwalk_unmap(src);
 		scatterwalk_unmap(assoc);
-		scatterwalk_done(&src_sg_walk, 0, 0);
-		scatterwalk_done(&assoc_sg_walk, 0, 0);
+		scatterwalk_advance(&src_sg_walk, req->src->length);
+		scatterwalk_done(&src_sg_walk, req->src == req->dst, 0);
 	} else {
-		scatterwalk_map_and_copy(dst, req->dst, 0, tempCipherLen, 1);
-		kfree(src);
+		scatterwalk_map_and_copy(dst, req->dst, req->assoclen,
+					 tempCipherLen, 1);
+		kfree(assoc);
 	}
 	return retval;
 }
@@ -1188,36 +1139,6 @@ static int rfc4106_decrypt(struct aead_request *req)
 
 	return crypto_aead_decrypt(subreq);
 }
-
-static int helper_rfc4106_encrypt(struct aead_request *req)
-{
-	int ret;
-
-	if (unlikely(!irq_fpu_usable())) {
-		WARN_ONCE(1, "__gcm-aes-aesni alg used in invalid context");
-		ret = -EINVAL;
-	} else {
-		kernel_fpu_begin();
-		ret = __driver_rfc4106_encrypt(req);
-		kernel_fpu_end();
-	}
-	return ret;
-}
-
-static int helper_rfc4106_decrypt(struct aead_request *req)
-{
-	int ret;
-
-	if (unlikely(!irq_fpu_usable())) {
-		WARN_ONCE(1, "__gcm-aes-aesni alg used in invalid context");
-		ret = -EINVAL;
-	} else {
-		kernel_fpu_begin();
-		ret = __driver_rfc4106_decrypt(req);
-		kernel_fpu_end();
-	}
-	return ret;
-}
 #endif
 
 static struct crypto_alg aesni_algs[] = { {
@@ -1389,27 +1310,6 @@ static struct crypto_alg aesni_algs[] = { {
 			.geniv		= "chainiv",
 		},
 	},
-}, {
-	.cra_name		= "__gcm-aes-aesni",
-	.cra_driver_name	= "__driver-gcm-aes-aesni",
-	.cra_priority		= 0,
-	.cra_flags		= CRYPTO_ALG_TYPE_AEAD | CRYPTO_ALG_INTERNAL,
-	.cra_blocksize		= 1,
-	.cra_ctxsize		= sizeof(struct aesni_rfc4106_gcm_ctx) +
-				  AESNI_ALIGN,
-	.cra_alignmask		= 0,
-	.cra_type		= &crypto_aead_type,
-	.cra_module		= THIS_MODULE,
-	.cra_u = {
-		.aead = {
-			.setkey		= common_rfc4106_set_key,
-			.setauthsize	= common_rfc4106_set_authsize,
-			.encrypt	= helper_rfc4106_encrypt,
-			.decrypt	= helper_rfc4106_decrypt,
-			.ivsize		= 8,
-			.maxauthsize	= 16,
-		},
-	},
 #endif
 #if IS_ENABLED(CONFIG_CRYPTO_PCBC)
 }, {
@@ -1526,6 +1426,22 @@ static struct crypto_alg aesni_algs[] = { {
 
 #ifdef CONFIG_X86_64
 static struct aead_alg aesni_aead_algs[] = { {
+	.setkey			= common_rfc4106_set_key,
+	.setauthsize		= common_rfc4106_set_authsize,
+	.encrypt		= helper_rfc4106_encrypt,
+	.decrypt		= helper_rfc4106_decrypt,
+	.ivsize			= 8,
+	.maxauthsize		= 16,
+	.base = {
+		.cra_name		= "__gcm-aes-aesni",
+		.cra_driver_name	= "__driver-gcm-aes-aesni",
+		.cra_flags		= CRYPTO_ALG_INTERNAL,
+		.cra_blocksize		= 1,
+		.cra_ctxsize		= sizeof(struct aesni_rfc4106_gcm_ctx),
+		.cra_alignmask		= AESNI_ALIGN - 1,
+		.cra_module		= THIS_MODULE,
+	},
+}, {
 	.init			= rfc4106_init,
 	.exit			= rfc4106_exit,
 	.setkey			= rfc4106_set_key,